1. Field
The present invention relates generally to fluid management during a surgical procedure, and more specifically to monitoring fluidics parameters and acting to prevent potential harm during a surgical procedure, such as an ocular surgical procedure.
2. Background
Surgical systems, such as phacoemulsification systems for ophthalmic surgery, require an infusion of fluid into a patient's eye while the surgery is being performed. Accurate management of such fluid infusion is critical to the procedure. In the phacoemulsification surgical context, the surgeon employs a phacoemulsification machine that controls fluid flow to the ocular region of the patient. If fluid flow is inadequate during the ocular surgical procedure, an adverse and potentially catastrophic situation can develop, possibly causing severe damage to the patient.
Fluid flow is typically controlled during an ophthalmic or ocular surgical procedure in part by the phacoemulsification machine adjusting the height of an infusion bottle or other irrigation fluid source. Other parameters or attributes of the fluid path can materially affect fluid flow to the eye, including but not limited to incision size and the dimensions of the fluid delivery device, such as outer diameter of the needle being employed in an ocular surgical handpiece, inner diameter of the needle and size(s) of other fluid passages in the fluid path, and incision leakage effects. As an example, different sleeves provided on different phacoemulsification handpieces can have varying fluid path diameters and consequently can deliver different amounts of fluid.
Newer phacoemulsification devices also employ different types of pumps, including volumetric pumps (e.g. peristaltic pumps) and vacuum pumps (e.g. Venturi pumps). Certain surgeons prefer to use one type of pump over another in certain surgical situations, while others prefer to operate by occasionally switching between pumps. Pump settings and accessories, such as phaco needle tip size and lumen size, can be matched to the expected fluid characteristics of the system. For example, if a surgeon is expecting to use only peristaltic pumping to infuse the eye, she may employ a certain sleeve having a particular gauge (fluid opening size). If switching between pumps is desired, such functionality can be provided to the surgeon, enabling him to manually or automatically switch between pumps at certain times or under certain conditions, depending on the risks involved.
Other issues may arise, such as in the situation where the surgeon employs an incision knife during the surgical procedure. Problems may arise when the opening made by such an incision knife is large relative to the inner and outer diameters of the sleeve employed on the handpiece and the outer diameter of the tip employed. Additionally, fluid flow is typically varied in these procedures by varying height of a BSS bottle, and changes in bottle height can affect the flow into and through a sleeve and tip when employed in the presence of different types of pumps.
Certain combinations of the foregoing fluid devices, parameters, and settings employed can result in unforeseen conditions. As an example, when switching between peristaltic and Venturi pumps, employing a certain phaco tip and sleeve in the presence of a particular incision size and using a certain bottle height, inadequate fluid may be provided to the ocular region. Such an arrangement can, in absolute worst case scenarios, result in anterior ocular chamber collapse or iris prolapse when switching between pump functions.
The difficulty for the surgeon is knowing when these potentially hazardous conditions may occur. Surgeons and other operating room personnel are typically focused on various other tasks, and personnel present may simply not know when a dangerous situation may occur, or when a potentially harmful set of conditions is present.
There is therefore a need in the art for techniques and devices that can provide efficient and effective notice to the surgeon that a potentially dangerous condition may occur with respect to fluid flow to the eye of the patient. In certain instances, there may be a need to alter functionality in the case of a potentially dangerous situation. It would therefore be beneficial to provide a design that overcomes fluid management issues present in systems known in the art.